The militants of Islamic State have reportedly struck a deal with moderate Syrian rebels not to fight each other and focus on toppling the government. Some reports say the deal was brokered by the Al-Nusra Front, an Al-Qaeda branch in Syria.

The IS, formerly known as ISIS/ISIL, is preparing its forces in
Syria for likely bombings by the US, which now considers itself
at war with the extremist movement. In addition to spreading out
from their known facilities, the group that took over portions of
Syria and Iraq to build a caliphate is apparently seeking to
safeguard itself from attacks of other armed groups in the
war-torn country.

According to the Syrian Observatory for Human Rights, a
London-based conflict watchdog, the IS has signed a
non-aggression pact with moderate fighters, who control the Hajar
al-Aswad neighborhood of Damascus.

Under the deal, "the two parties will respect a truce until a
final solution is found and they promise not to attack each other
because they consider the principal enemy to be the Nussayri
regime," AFP reported. “Nussayri” is a derogatory
name for the Shiite Alawite sect, to which Syrian President
Bashar Assad and many of his officials belong.

According to Orient Net, the truce is meant to stop fierce
fighting that engulfed the neighborhood for over 40 days and was
brokered by the Al-Nusra Front, an Al-Qaeda affiliate that has
frequently clashed with the Islamic State, which itself
splintered from the terrorist network to pursue an independent
struggle for power in the region.

The moderate rebels who signed the deal include four distinct
groups, including the US-backed Syria Revolutionary Front,
reported Charles Lister, an analyst at the Brookings Institute.
The SRF was considered moderate enough to merit the West’s
support and a part of the Free Syrian Army, a loose coalition of
secular and moderate groups fighting to topple the Assad
government with the blessing of Washington.

In an earlier interview with the Independent, SRF leader Jamal
Maarouf said that Al-Qaeda was not his problem and that he would
welcome “anyone who fights against the regime inside
Syria."

The news comes as the US Congress is considering a $500 million
request from the Obama administration to train and arm moderate
rebel groups in Syria. Washington refuses to send its own troops
on the ground against the IS and will limit its military action
to reconnaissance and airstrikes instead.

This means that the shooting part of the war against the
Islamists, which Obama declared, would have to be fought by
forces like the Kurdish militia, which already receives arms from
the US and some European countries, and moderate Syrian rebels.
The reported alignment of supposedly moderate SRF with America’s
enemies raises the question whether Washington would be able to
vet the recipients of its military aid to ensure that those arms
and training would not be eventually used against it.

The Obama administration seems to be confident of this.

"We have been working with the Syrian opposition now for a
couple of years, providing them assistance, non-lethal at first
but then we [now] provide them with some military assistance, so
we know them better today than we did a year, two years
ago," deputy national security adviser Ben Rhode told The
Huffington Post before the news of the deal broke.

"If we were to try to run a play with Assad, we would ensure
that they were turned against us, and in fact we would be taking
sides in a sectarian war against one side,” he added.